Electric-arc lamp



(No Model.)

C. G. PERKINS.

ELECTRIC ARG LAMP.

Patented Mar.20, 1883.

2l/leasen N. PEYERS. Mmmm www D. C.

UNITED STATES PATENT OEEICE.

CHARLES G. PERKINS, OF GAMDEN, NEW JERSEY.

ELECTRIC-ARC LAMP.

SPECIFICATION forming part of Letters Patent No. 274,370, dated March 20, 1883.

Application tiled May 10, i882. (No model.)

To all whom it may concern Be it known that I, CHARLES G. PERKINS, of the city of Camden, in the county of Camden and State of New Jersey, have invented a new and useful Improvement in Electric Lamps, of which the following is a specification, reference being had to the accompanying drawings, forming a part ofthe same.

Figure lis a vertical elevation, partly in section, representing the working construction and general arrangement ot my invention. Fig. 2 is a plan view of Fig. l. Figs. 3 are front and side views, showing the construction ofthe arms e, e', aud c, as shown in Fig. l. Figs. 4 are illustrations in detail giving different views ofthe parts of which the frictionband i 2 consists. Fig. 5 is a view in detail of therack and pinion seen in Fig. l and Fig. 6 is a modified form of Fig. et, in which the friction-band and roller g are dispensed with, the right-angular projection upon arm c resting upon the disk-pin, as shown, acting as a substitute therefor. Fig. 7 represents a moditied construction ot' the friction-band shown in Fig. 4, in which the arm c is dispensed with, the extension c, which may be attached to the armature b, loosening or tightening its hold upon the inclosed disk according to the varying strengthof magnetism inc c2.

This improvement relates to 'that form of electric lamp in which the voltaic arc is employed by the passage of a current of electricity between two electrodes 5 and it consists in a novel construction of a lever-brake and encirclingfriction-band embracing the periphery of a rotatory disk, the lever being attached to the sliding core of an axial electro magnet or magnets, the whole heilig for the purpose of regulatingthe distance between the carbon points, so that the slightest variation of resistance in the arc will result in an instantaneous response ot' certain mechanism, which will producea sufficient movement of the positive electrode as consumption takes place to maintain a suitable distance between the points for obtaining alight ofthe required intensity.

In combination with the above, my improvement further consists of a shunt-resistance arrangement whose object is to establish the continuity of the circuit in the event of an accident occurring to either of the electrodes by breakage or otherwise, some such arrangement being necessary when there are a number of lamps to be operated in series. It is necessary, also, that this shunt should have a resistance about equal to the normal resistance of the are.

When itis required to put the lamp in circuit, the conductors from an electrical source are connected to the binding-screwslt h, when a current of electricity will pass round the helices of magnet a', which is wound with coarse wire and forms a continuous part of the conductor leading to the positive electrode. The sliding core b is thereby drawn down into its socket in magnet a', and with it the lever c, which is attached to this sliding core at l in such a manner as to allow the lever c suflicient play from its center as the sliding core is alternately attracted by the electro-magnets to meet the requirements of the case. As a result of the attractive force of magnet a' upon sliding core b, the arm c of leverc, with its roller g, presses upon the hinged part ot' encircling friction-band z'. This friction-band, as will be seen from the drawings, is composed ot' two parts, 17452, being hinged together at 133, and, as will be further observed, the divided part is slightly turned up at g2, so that the slightest movement ot' lever c will instantaneously exercise a suflicient pressure upon the periphery of the pinion-disk j2 to prevent the sliding rack j descending too rapidly or too far; also for the purpose of allowing the rollerg to move only a very little distance before the required degree of pressure is brought to bear upon hinged part t" at g2.

Inclosed within or encircled by the frictionband t" i? is a piniondisk,j2, the encircling friction-band embracing the periphery of 'the same. rlhe pinion j3 works in conjunction with a rack,j', for the understood purpose of parting the carbon electrodes. As the carbons are consumed the resistance of the arc increases, whereby magnet a loses some of its power. The core b will then ascend a certain distance, being attracted by magnet a2, which now becomes stronger than a. (a2 is wound with ne wire and is placed in a derived circuit.) The altered position of lever c relieves the pressure it exercises upon piniou-diskj2 by the embracing-band i' i2 when the positive electrode, with the sliding rack, descends a prescribed distance, when the normal resistance of the arc is re-established and the required intensity of light secured. The small weight l is fixed to the band i i2, its object being to hold the friction-band gently pressed against and in readiness for the performance ofthe function assigned to lever c, with its arm e, having the roller g.

In the mechanism base-plate of the lamp, directly under the brake-wheel, is fixed a pin, 2, in such a position that a corresponding pin, l, on the friction-band i2 will meet the same when the lamp is in operation, thereby preventing the friction-band revolving too far, as it necessarily would in the absence of such an arrangement.

As before stated, the shuntresistance is brought into operation when either of the electrodes are thrown out of circuit. Its action is as follows: When an electrode is put out of circuit, magnet a', which is a continuous part of the conductor leading to the positive electrode, loses its power altogether. The sliding core b then leaves its socket inv magnet a and ascends to the limit of its distance into that of magnet a2, (i t will be remembered that the latter magnet, being in a derived circuit, is not affected lby either of the electrodes being put out of circuit,) for the reasons already stated. The contact-weight m, in consequence ot' the ascent of sliding core b to the limit of its distance, then falls upon the spring n, and at the same time makes connection with one end of the shunt-resistance o at 0. On referring to the drawings it will be seen that spring n is connected with the positive pole of the lamp. N ow, if a current oi' electricity passes along this spring,which is touched by contact-weight m,it passesin at the positive end of the shuntresistance, and the other end being connected with the negative pole of the lamp, the circuit is complete, and the other lamps in the same series remain unaffected. The contact-weight must of course be insulated from the metallic lever-extension e', towhich itis secured. When the electrodes are again brought together, magnet a is once more energized and the arc reestablished, because the shunt o is of higher 5o resistance than the electrodes when the two points touch, and the current will find the passage of least resistance. The shunt-resistance is therefore thrown out of circuit in consequence of the energized condition of magnet a 55 and the resulting altered position of lever c, as already described.

Having thus described my invention, wh at I claim as new, and desire to secure by Letters Patent, is

l. In electric-arc lamps, the mechanism for regulating the distance to be maintained between the electrodes, which consists in the combination of the electro-magnets a a2, having the sliding core b, to which is attached the 65 lever c, having the arm e, with roller g and arm e', the divided friction-band i i2, embracing the revolving dskjz, and the weight Z, in conjunction with a rack and pinion connected with the positive electrode ofthe lamp, substantially as 7o described.

2. In electric-arc lamps, the combination ot the divided friction-band i i2, hinged at i3 and turned up at g2, the rotatory disk jZ, with the roller g, rack g', and pinion js, substantially as 7 5 described, and for the purpose set forth.

3. In electric-arc lamps, the combination of the encircling friction-band i' i2, embracing the periphery' of the disk j3, and friction band weight L, with the lever c, arm c, roller g, arm 8o e', shunt-resistance 0, and spring a, substantially as described.

et. In electric-arc lamps, the combination of the encircling friction-band i i2 with the arln e and roller g, arm c' and Weight l, and pins l 85 and 2, substantially as described.

CHARLES G. PERKINS.

Witnesses CHARLES RICHTER, BERNHARD ScHRoEDER. 

